javascript - ExtJS:如何在函数中更改组件`labelStyle`？

tl / dr：
setter没有任何labelStyle。那么如何更改函数的值呢？

我有一个afterrender侦听器，旨在将fieldLabel的颜色设置为白色，并设置emptyText而不是fieldLabel，同时我需要将fieldLabel的颜色更改为白色！因此，我需要访问当前组件的lableStyle属性。我尝试进入config，但找不到。也尝试使用Ext.apply()设置相关组合的属性，但这也不起作用。

我如何在这里实现目标？

//Related component `listeners`;
listeners   : {
        afterrender: 'removeLabel',
        focusenter: 'createLabel'
    },

//Related function;
removeLabel: function () {
        let formComponent = ['foocombobox', 'bartextfield', 'zetdatefield'];

        Ext.each(formComponent, function (eachComp) {
            let currentComp = Ext.ComponentQuery.query(eachComp)[0];

            if (currentComp.value === '')) {
                let currentLabel = currentComp.fieldLabel;
                currentComp.setEmptyText(currentLabel);

                //This can not work because of I've reach constructor config. So how can I reach?
                //currentComp.labelStyle  = "color:red;";

                //I tried to manipulate through Ext.apply but did not effect;
                //Ext.apply(currentComp, {labelStyle: "color:red;"});


            }
        });
    },

最佳答案

我通过currentComp.labelTextEl.dom获取dom节点，然后运行setAttribute函数：
FIDDLE

if (!currentComp.value) {
    urrentComp.setEmptyText(currentComp.fieldLabel);
    currentComp.labelTextEl.dom.setAttribute('style', 'color:white;');
}